Dyeing of cellulose derivatives



Patented June 18, 1935 PATENT 0F FICE 2,005,303 DYEING 0F CELLULOSEDERIVATIVES Louis Spiegler and Henry assignors to E. I. du Pont dewaukee, Wis.,

Nemours & Company poration of Delaware No Drawing. Application JanuarySerial No. 653,482

8 Claims.

This invention relates to the dyeing or coloring of organic derivativesof cellulose. More particularly, this invention deals with theapplication of nitrogenous benzacridone derivatives,particularlynitro-acridones as dyestuffs for cellulose esters, such ascellulose acetate, cellulose ethers, or related fibers.

We have found that simple acridone compounds which are substituted by anitro group form good dyestuffs for cellulose ester and related fibers,imparting thereto colors within the range of greenish yellow to orange,depending on the position of the nitro group and on the nature of othersubstituents which may be present in the nucleus.

of particular value are acridones bearing a nitro group in positionortho or para to the meso NH group, hereinafter referred to as the 1 or3 positions respectively. See formula below. These in turn may befurther improved as to shade, affinity, or fastness qualities bysubstitution, preferably in the phenyl ring opposite to that bearing thenitro group.- The rule, however, is not exclusive, since we found manyvaluable dyestuffs among those which have substituents in the same ringwith the nitro group, or in both rings. Among the substituents, any ofthose commonly met with in aromatic nuclear substitution may be used.The group comprises inorganic as well as organic radicals, such aschloro, bromo, nitro; amino, methyl, methoxy, ethoxy, hydroxy, andothers.

The above efiect is particularly surprising'in view of the circumstancethat the simple acridone compounds have not been known to this date ashaving dyeing qualities. The acridone compounds found in the art havegenerally been used as pharmaceutical compounds or for the synthesis ofacridines, which in turn were used for the synthesis of therapeuticcompounds and a limited series of dyestufls for mordanted fiber. Thatacridone derivatives substituted by nitro groups would have afiinity forcellulose esters or related fibers was entirely unforeseen.

The application of our novel dyestuffs to the fiber may be effected inany of the known man ners for applying water insoluble or sparinglysoluble dyestuffs to celanese fibers. Generally, these methods involveeffecting, either mechaniular procedure,

R. Lee, South Mil- Wilmington, Del, a corcally, or by the aid ofemulsifying or dispersing agents, a dispersion of the dyestuif in waterand then steeping the fiber in this suspension and warming up to atemperature not above the boiling point of water.

Without limiting our invention to any particthe following example, inwhich parts by weight are given, will serve to illustrate our preferredmode of operation.

Example The particular color selected, for instance, 1- nitro-acridone,may be made up into a wet dyestufl paste by milling 10 parts of the samewith 90 parts of water until uniformly dispersed.

Alternatively, the color may be made up into a dry dyestufiipowder bymilling 10 parts of the color compound, say l-nitro-acridone, with 90parts of inert, water-soluble material such as sugar, soap, Glauberssalt, common salt, dextrine, or a mixture of these, with orwithout adispersing agent, such as an alkylated naphthalene-sulfonic acid or asalt thereof, sulfonated ricinoleic acid, a sulfonic acid of theabietene family'or a salt thereof, rosin soap, aldehyde-sulfo-arylcondensation products, dry sulfite waste concentrates, etc.

1 part of the above dyestufi' paste or powder is stirred up in parts ofa 10% soap solution to a smooth paste. To this, 50 parts of hot waterare added, and stirring is continued until the color is effectivelydispersed. The paste is then diluted with water to a total of 500 parts.A suitable volume of the above suspension, depending on the desiredstrength of the dyeing and the weight of cellulose acetate to be dyed,is diluted with warm water (at 120 F.) to fifty times its own volume.The cellulose-acetate fiber, which has preferably first been subjectedto a light soaping at 140 F. in a soap solution, is now introduced, andthe dye bath ismaintained at 120 F. for 5 minutes. It is then warmed upto 160 F.-200 F. and held at this temperature for an hour. The fiber isthen removed, rinsed and dried.

If the color in the above procedure was l-nitroacridone, the fiber willbe found dyed a bright yellow color of good fastness to light, acid andalkali. If other acridone compounds are used, fications, withoutdeparting from the spirit of the results will be found as indicated inthe 1301- this invention.

lowing table. The positions of the substituents We claim:

in this table are as indicated in the following 1. The process whichcomprises dyeing cellulose f rmul ester fibers with an acridone compoundof the 6 NH general formula:

p/ 10 \\/1\ NH N0, Qu z d a n 10 Color on cellulose Aflinity Fastnemacetate iorflber tollgbt 1-nltro-acrldone-. Excellent. Excellent.2-nitro-acrldone- Weak.-..- Good. 3-nltrc-acridone Weak..--- Goodl-methyl-lt-nitro-aerldone Yellow Weak".-- l-nitro-iiemetbyl-acr0range-yellow Excellent- Good. 1-nitro-3-methoxy-acridone' Creme Fair...Good. Brominated l-nitro-acridone (mono)" Greenish yellow--- Excellent.Good. Bromlnated l-nitro-acridone (di)" Greenisli yellow-.... ExcellentGood. 1,3-dinltro-acridone Good. Good. l,8-dinitroacridoue Excellent-Good.

1,9-dinitro-acridone' co Excellent. 3,7-dinitro-acridone Ye ow Weak"-..2,1-dinitro-acridone" Greenisli yellow.- Good Good.I-nitro-Wmethoxy-acridone' Orange-yellow Good Good.l-nitro-7-ethoxy-ucridone' Golden orange Gcod Good.z,y,l-trinitro-acridone" Orange-yellow Good. Weak.

-The monoand di-brominated l-nitro-acridones acridone- In the case ofthe compounds marked the 2. The process which comprises dyeing cellulosesynthesis briefly consists of condensing anthraester fibers with anacridone compound of the nilic acid by the aid of copper and acidabsorbgeneral formula: ing agents with the corresponding substitutedbromoor chloro-benzene, or by condensing ortho- NH halogen-benzoic acidwith a substituted aniline. The resultingsubstituted.diphenylamine-2-carl boxylic acid is ring closed in knownmanner to give the corresponding acridone. (Compare formation ofQ-nitro-acridone, Clemo, Perkins and gzg gggg of the Chemical Societywherein X and Y stand for hydrogen or a subi the case of the compoundsmarked (H) stituent oi the group comprising halogen, nitro,l-nitro-acridone is first prepared and then subi alkyl alkoxy hydmxy' 3.The process of dyeing cellulose ester fibers jected to furthertreatment, such as bromination or nitration to the desired stage, as thecase 3'31? cmpnses applymg thereto m 1) f h 1- y e The urt er mtmtmn ofmm) 4. The process of dyeing cellulose ester fibers done may be carriedout according to the process described in Berichte, vol. 64, pages2383-2386. whlch mpr15es aPPlYmg there'w 9411mmmay be pmduced bybrominating the m- 5. Cellulose ester material colored withanacriacridone in acetic acid at reflux temperature, done compound 85defined in Claim using theoretical amounts of bromine. 6. Celluloseester material colored with an acri- The dyestuffs of our novel seriesexhibit sudone compound as defined in claim 2.

perior fastness to acid and to alkali. They do 7. Cellulose estermaterial colored withanacrinot dye cotton or wool, and are thereforeexceldone compound as defined in claim 3.

lently adapted for dyeing union fabrics, that is, 8. Cellulose estermaterial colored with an acrifabrics containing threads of cotton orwool and done compound as defined in claim 4.

threads of cellulose acetate, where it is desired to color the latteronly. LOUIS SPIEGLER.

It will be understood that our invention is sus- HENRY R. LEE. ceptibleto a wide range of variations and modi-

